I will say it is much more relaxing to be in the submissive role even when receiving corporal punishment than to be a top.
A top that knows more than beating their submissive to a pulp has a much more difficult and tiring job to do both physically and mentally.
When I am the top, I often wear heels, corsets, latex wear, leather wear, velvet, etc, but when I am the bottom, I am usually naked, leaving all my parts open for torment and occasional pleasure for when my husband feels I have been good or deserving of a perk.
I don't really get into the school girl role, but frilly short skirts that require lifting before a butt blistering paddling sounds good. A little lingerie leaving your sensitive areas exposed is also good for other activities in a submissive role.
You get into s submissive mindset [you'll like this] by getting into a submissive mindset. If you want to practice alone, you can tie your ankles together and then wrists together. Then put on a blindfold and just lay absolutely still. Set a timer for a predetermined amount of time and just settle into the situation. DO NOT release yourself early. If you are very disciplined, you can force yourself to simply lay absolutely still without the restraints--even if you have to scratch your nose--suffer baby!
I just noticed you are from The Netherlands. Its too bad they don't have the Europerve event anymore--at least I haven't seen anything about it for a couple of years. I would love to take part in that again.